The present invention relates to an air bag device comprising a bag which develops to protect a person on board during a collision of a vehicle, an inflater which generates gas for expanding the bag, and an electronic control unit which operates the inflater.
Recently, an air bag device which expands a bag to protect a person on board during a collision of a vehicle, an inflater which generates gas to expand the bag, and an electronic control unit (hereinafter referred to as ECU) including an electronic acceleration sensor that performs collision judgements of the vehicle on the basis of signals from the sensor, are provided in a steering wheel such that the electronic acceleration sensor for detecting the collision of the vehicle is in corporated in the steering wheel.
More specifically, as shown in FIG. 22, a housing 3 containing an ECU is fastened on a steering wheel 6 by bolts 5, and a bag 2 is clamped between an outer peripheral portion 1a of an inflater 1 and a retainer 7. The outer peripheral portion of the inflater 1, the bag 2 and the retainer 7 are fastened on a stay 8, and the stay 8 and a pad 9 are fixed on the steering wheel 6.